Head Diameter Research Articles

Paper 18: The Pendulum Has Swung: A 14-Year Analysis of Patients Presenting for Failed Hip Arthroscopy Shows Rising Incidence of Cam Over-Resection and Decreasing Incidence of Under-Resection

Background: There is a paucity of literature regarding prevalence of femoral resection in the setting of revision hip arthroscopy. Few studies have examined different types of resections and their presentation. Purpose: To describe the prevalence of femoral resection types in the setting of revision hip arthroscopy for residual femoroacetabular impingement syndrome (FAIS) symptomatology. Methods: A search of the institutional prospective registry was performed for patients who presented for evaluation of failed previous arthroscopy between February 2008 and June 2022, and subsequently underwent revision arthroscopy. AP and Dunn view radiographs were reviewed from our study population. On the basis of measurements on both radiographs, patients were divided into 3 categories: overresection (OR) in which the resection measured 5% or more of the femoral head diameter, underresection (UR) in which residual CAM morphology was found (alpha angle >60°), and neutral resection, alpha angle less than 60° and no overresection. Both AP and Dunn radiographs were used to identify over- and under- resections. Results: A total of 622 hips were reviewed and measured on both AP and Dunn radiographs. Of the 622 hips, there were 373 right and 249 left hips. The average age was 33.7 ± 12.0, and the average body mass index (BMI) was 26.0 ± 5.2. Three hundred sixty-five hips were classified as UR and 265 hips as OR. The mean prevalence rates from 2008 to 2022 for neutral resection, over-resection and under-resection were 48.1%, 20.3%, and 31.6%, respectively. The prevalence rates of UR have decreased since 2008, while prevalence rates of OR have increased concomitantly. The steadily decreasing prevalence rates of UR was negatively correlated with the increasing OR ((R=-0.829, P<.0001), as well as with neutral resections (R=-0.735, P=0.002). The ratio of UR to OR reversed entirely, from 4:1 in 2010, to 1: 2.3 ( P < 0.00001) in 2020. Conclusions: Amongst patients presenting for failed hip arthroscopy over the last 14 years, the pendulum has swung from under-resection towards over-resection. Indeed, as of 2020, over-resections were more than twice as common as under-resections. This may be a result of heightened awareness in FAIS, and previous literature emphasizing the risks of under-resection. As we gain increased understanding of the risks of over-resection, the findings of this study highlight the importance of achieving an anatomical spherical resection.

Winter cover crop suppression methods influence on sunflower growth and rhizosphere communities.

Sunflower (Helianthus annuus L.), a vital crop for global vegetable oil production, encounters sustainability challenges in its cultivation. This study assesses the effects of incorporating a winter cover crop (CC), Avena sativa (L.), on the subsequent growth of sunflower crops and the vitality of their rhizosphere microbial communities over a two-year period. It examines the impact of two methods for suppressing winter CC-chemical suppression using glyphosate and mechanical suppression via rolling-both with and without the addition of phosphorus (P) starter fertilizer. These approaches are evaluated in comparison to the regional best management practices for sunflower cultivation, which involve a preparatory chemical fallow period and the subsequent application of starter P fertilizer. The methodology utilized Illumina sequencing for the analysis of rhizosphere bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) amplicons. Findings indicate a significant improvement (9-37%) in sunflower growth parameters (plant height, stem diameter, head diameter, and head dry weight) when cultivated after glyphosate-suppressed winter CC compared to the chemical fallows. Conversely, rolling of winter CC generally negatively affected sunflower growth. Rhizosphere bacterial communities following chemical suppression of winter CC showed greater Pielou's evenness, indicating a uniform distribution of species. In general, this treatment had more detrimental effects on beneficial sunflower rhizosphere bacteria such as Hymenobacter and Pseudarthrobacter than rolling of the winter CC, suggesting that the overall effect on sunflower growth may be mitigated by the redundancy within the bacterial community. As for fungal diversity, measured by the Chao-1 index, it increased in sunflowers planted after winter CC and receiving P fertilization, underscoring nutrient management's role in microbial community structure. Significant positive correlations between fungal diversity and sunflower growth parameters at the reproductive stage were observed (r = 0.41-0.72; p < 0.05), highlighting the role of fungal communities in plant fitness. The study underscores the positive effects of winter CC inclusion and management for enhancing sunflower cultivation while promoting beneficial microbes in the crop's rhizosphere. We advocate for strategic winter CC species selection, optimization of mechanical suppression techniques, and tailored phosphorus fertilization of sunflower to foster sustainable agriculture.

Social inequality and body mass differences in two post‐Medieval Dutch populations

AbstractAdult body mass is largely related to nutrition levels, which can be affected by external stressors, such as diet, environment, and disease. High‐status and low‐status groups likely had very different nutrition and stress experiences, which might result in differences in population's body mass. Since inequality between social statuses prevailed in Europe in the post‐Medieval period, did these differences result in body mass variations between high‐status and low‐status populations in the Netherlands? In order to answer this question, this research compared body size of two post‐Medieval urban skeletal collections with different social statuses from the Eusebius cemetery of two cemeteries of the 17th–19th centuries: the Arnhem and the Broerenkerk church of Zwolle, the Netherlands. Social statuses of the two collections are estimated based on the burial locations, grave goods, and historical records. Body mass was estimated using both femoral head diameter method and stature/bi‐iliac breadth method. Results have shown no statistically significant differences in body mass between the two samples. Therefore, this research suggests that inequality in post‐Medieval Dutch society did not result in observable population body mass differences in the skeletal collections of different social status groups. It cannot, however, prove that social inequality in populations did not impact body size or health more broadly.

Unlocking the Genetic Potential by Assessing Combining Ability and Heterosis for Yield and its Component Traits in Sunflower (Helianthus annuus L.)

The present investigation was executed with two lines and 12 testers along with 24 F1s and check NDSH 1012 for six yield and its component traits to ascertain the combining ability and heterosis. The analysis of variances showed highly significant differences among the parents for all the characters except for seed yield per plant and oil content implying the presence of significant variability and diversity among the parents. Among the two lines, ARM-243A was observed as best general combiner for head diameter, seed yield per plant and oil content. The tester, NDI-56 was found ato be good general combiner for head diameter and seed yield per plant. Out of 24 F1s evaluated, two crosses viz., CMS-17A X NDI-35 and CMS-17A X NDI-52 were recorded as good specific combiners for seed yield per plant and head diameter, respectively. The heterosis analysis revealed that 10 hybrids recorded positive significant mid parent, better parent and standard heterosis for seed yield per plant. Hence, the crosses CMS-17A X NDI-35 and CMS-17A X NDI-52 are advanced for direct selection to increase vigour gain.

Effect of different organic sources and time of manuring on the growth, yield and quality of cabbage (Brassica oleracea var. capitata)

A field experiment was conducted during the rabi season of 2022-2023 at the Instructional cum Experimental Farm, Nagaland University, School of Agricultural Sciences, Medziphema campus to evaluate the “Effect of different organic sources and time of manuring on the growth, yield and quality of cabbage (Brassica oleracaea var. capitata). The experiment consisted of 15 treatments laid out in RBD with three replications. Result of the experiment clearly revealed that application of 75% N through VC one day before transplanting + 25% N through VC 20 DAT obtained maximum growth parameters, quality parameters and yield parameters with plant height (29.69 cm), stem diameter (2.73 cm), plant spread (50.37 cm), head compactness (34.70 cm), ascorbic acid content (9.16 mg 100-1g) and protein content (2.53%), head diameter (13.48 cm), head size (152.41 cm2), gross head weight (1416.67 g), net head weight (865.03 g), yield per plot (10.36 kg) and projected yield per hectare (24.03 t). Highest available N (301.66 kg ha-1) was recorded in T15 (RDF) while T4 (100% N through FYM 10 days before transplanting) recorded the maximum available phosphorous (49.45 kg ha-1). Maximum available potassium (218.89 kg ha-1), organic carbon (2.63%) and CEC (14.66 meq 100-1g) were recorded from T3 (75% N through VC one day before transplanting + 25% N through VC 20 DAT). Economics of treatments was calculated and T3 (75% N through VC one day before transplanting + 25% N through VC 20 DAT) recorded highest net return (Rs 5,03,900).The above findings suggest that the application of vermicompost can be effectively used for obtaining higher yield, improve soil fertility and higher net returns for organic cabbage cultivation.

Influence of Different Rates of Nitrogen and Sulfur on Growth, Yield and Yield Attributes of Cabbage (Brassica oleraceae L.)

The field experiment was conducted at Lovely Professional University, Phagwara, during rabi season on the sandy loam soils to study the influence of different rates of nitrogen and sulfur on growth and yield attributes of cabbage (Brassica oleraceae L.). The experiment was laid in Factorial Randomized Block Design (FRBD) consisting of eight treatments and three replications viz. (N1: 0 kg N per ha, N2: 100 kg N per ha, N3: 125 kg N per ha, N4: 150 kg N per ha, S1: 0 kg S per ha, S2: 30 kg S per ha, S3: 60 kg S per ha and S4: 90 kg S per ha). The different growth and yield attributes viz. plant height (cm), number of unfolded leaves per plant, diameter of cabbage head (cm), weight of cabbage head (kg) and yield of cabbage (t/ha) were recorded at different growth stages and at the time of harvesting. The results revealed that the application of 150 kg nitrogen and 90 kg sulfur per hectare gave the maximum values in all the growth and yield attributes compared to all the other treatments as well as control.

Study on erosion characteristics of turbine in sediment-laden river

Abstract Sediment erosion of hydro turbines is prevalent and serious in the mountain river region. The effect of operating head and particle diameter on sediment erosion was investigated in this paper. A Eulerian-Lagrangian approach was applied to numerically simulate the solid-liquid flow in a Francis turbine under the minimum, design and maximum heads. Five typical diameters (0.1, 0.3, 0.5, 0.7, 0.9 mm) were firstly determined based on field measurements at a hydropower station. After tracking the trajectories of sediment particles, McLaury model was selected to predict the erosion rate. The results show that sediment erosion regions of runner blades are similar under different operating heads, while the sediment erosion rates amplify significantly with the increase of operating heads. The erosion rate of blade suction side is significantly higher than that of pressure side because of the effect of inter-blade vortices between runner blades. Sediment diameters also play an important role in accelerating erosion rate, which indicate that setting up sedimentation tanks to settle large-size sediment particles is a powerful method to alleviate sediment erosion. This study can provide a reference for erosion estimation and operational maintenance of hydro turbines in mountain river region.

Growth and Yield of Lettuce (Lactuca sativa var. crispa) in Varying Irrigation Water Salinity and Leaching Fractions

This study aimed to determine the response of yield and yield parameters of the ‘Cospirina’ lettuce plant, known to be moderate salinity tolerant, to different levels of salt water applications and different leaching rates in the Eastern Mediterranean Region of Hatay Province, Türkiye. Lettuce was irrigated at three different irrigation water salinity levels (EC0 = 0.5 dS m-1-control, EC2 = 2 dS m-1, EC4 = 4 dS m-1) and four different leaching fractions (LF0 = 0%, LF1 = 10%, LF2 = 20%, LF3 = 30%). Irrigation water salinity was adjusted by adding different amounts of NaCl salt to the tap water (EC0, control) with an EC value of 0.5 dS m-1. Plant water consumption (PWC) increased as the leaching fraction increased but decreased as salinity increased. PWC ranged from 7.32 – 10.5 L for EC0, 7.0 – 8.46 L for EC2, and 5.0 – 6.46 L for EC4. The mean water use efficiency (WUEy) was calculated as 31.43 g L-1, 32.12 g L-1, and 34.77 g L-1 in EC0, EC2, and EC4, respectively. Lettuce yield decreased with increasing soil salinity and the leaching fraction. Yield ranged from 182 g plant-1 (EC4LF0) to 282 g plant-1 (EC0LF2). When soil salinity increased from 0.82 dS m-1 (EC0) to 1.31 dS m-1 (EC2) and 2.09 dS m-1 (EC4), yields decreased by 10% and 28%, respectively. Increasing salinity significantly decreased the root length, root width, leaf number, number of commercial leaves, leaf width, leaf length, and biomass, while commercial head length and commercial head diameter remained unaffected.

Prediction of TBM penetration rate for different surrounding rocks and cutter head diameters

The penetration rate (PR) of tunnel boring machines (TBMs) is often used to evaluate tunneling performance and predict construction period costs. However, most penetration rate (PR) prediction models are based on a single specific project, which leads to poor universality of the models.Furthermore, the value of the cutter head speed set for the prediction of the construction period in the survey and planning stages depends on manual experience and lacks theoretical guidance. Therefore, based on a set of engineering data from TBM of different surrounding rocks and diameters, this study statistically analyzed the distribution law of the cutter head speed (N) and the relationship between the field penetration index (FPI), geological parameters (uniaxial compressive strength (UCS) and the integrity coefficient of the rock mass (Kv)), and penetration (P). The results show that the FPI is strongly correlated with the geological parameters and the P. The geological and tunnelling parameters are the main factors affecting the penetration rate (PR). On the basis of this, prediction models of the FPI and P and a calculation model of the cutter head speed were developed, and a prediction model of the PR was obtained. The accuracy and reliability of this model were verified and analyzed for the EHe (EH) project. The average prediction error was 15.15 %.

Aplicación de nanoquitosán-yodo en lechuga y su efecto en la biofortificación, crecimiento y rendimiento

Iodine (I) is an essential element in human nutrition, however, in plants it is considered a beneficial element. The objective of the present work was to evaluate the application of nanochitosan-iodine complexes (NPsCs-I) on the biofortification of I in lettuce, in addition to its effect on growth and yield. Foliar application of NPsCs-I complexes was carried out on lettuce plants where plant height, head diameter, dry biomass and I content were measured. The application of NPsCs-I complexes had a significant effect on the yienld, since with the application of the complex at a dose of 5 mg L-1 of KIO3, it increased by 30.8% compared to the control. The foliar application of NPsCs-I complexes can provide an alternative for biofortification of I and biostimulation of lettuce plants.

Valuation of different organic and inorganic fertilizer combinations on the growth and yield of cabbage

abbage (Brassica oleracea var. capitata) is the most important winter leafy vegetable in the world and belongs to the Cruciferae family. An experiment was conducted at the Horticultural farm of Gauradaha Agriculture Campus, Tribhuwan University, Jhapa, Nepal from 26th December 2022 to 2nd April 2023 to evaluate the different organic and inorganic fertilizer combinations on the growth and yield of cabbage (Brassica oleracea var. capitata L. cv. Green coronet). The experiment was conducted as a randomized block design with 7 treatments replicated 3 times and the treatments are T1: 25-ton FYM/ha, T2: 25-ton PM/ha, T3: 25-ton FYM/ha + NPK (RDF), T4: 25-ton PM/ha + NPK (RDF), T5: 20-ton FYM/ha + 10-ton PM/ha + NPK (RDF), T6: 10-ton FYM/ha + 20-ton PM/ha + NPK (RDF) and T7: control. Significant variation was found among the treatments. The result showed treatment had a significant role in different parameters. T3- The highest number of leaves, T5- the highest (leaf area, weight with roots, net head yield, horizontal head diameter), T4-highest (plant height, gross yield), T6- highest (stem girth, vertical head diameter) was obtained. On the result basis T5 (20-ton FYM/ha + 10-ton PM/ha + NPK (RDF) can be adopted as sustainable crop production. This study not only provides valuable insights into optimizing cabbage production but also underscores the importance of tailored fertilizer combinations for sustainable agriculture. Furthermore, the findings contribute to the broader discourse on enhancing crop yield while minimizing environmental impact. By elucidating the efficacy of specific fertilizer blends, this research paves the way for more efficient and eco-friendly farming practices, thereby promoting food security and environmental sustainability on a global scale.

Factors related to collapse progression in Japanese Investigation Committee classification type B osteonecrosis of the femoral head.

This study aimed to identify factors related to collapse progression in Japanese Investigation Committee classification type B osteonecrosis of the femoral head (ONFH) and to identify patients who would benefit from surgical treatment. This study included 41 patients (56 hips) with type B ONFH with a minimum follow-up of threeyears. Based on a ≥ 3mm collapse progression in ONFH, we categorised patients into two groups: collapse progression and no collapse progression. Sagittal and coronal computed tomography images were used to measure the necrotic region relative to the intact femoral head diameter. The ratios of the necrotic regions of transverse and vertical diameter in coronal and sagittal images are defined as mediolateral transverse and mediolateral vertical, anteroposterior transverse and anteroposterior vertical, respectively. Demographic data and these imaging findings were compared between the two groups. We established a cut-off value for predicting collapse progression through receiver operating characteristic analysis and determined survival rates. Type B ONFH had a 17.8% collapse progression rate. The mediolateral transverse, mediolateral vertical, anteroposterior transverse, and anteroposterior vertical were significantly higher in the collapse progression group (P < 0.01). Mediolateral transverse was an independent risk factor of collapse progression (hazard ratio, 1.27; 95% confidence interval, 1.03-1.57; P = 0.03), with an optimal cut-off of 45.6%. The 5-year survival rates with collapse progression as the endpoints were 57.0 and 94.9% in the mediolateral transverse of ≥ 45.6 and < 45.6%, respectively. A mediolateral transverse of ≥ 45.6% predicts collapse progression in patients with type B ONFH.

Evaluation of the proximal femur using the digital photographs: Does change in proximal femur position due to anteversion affect the measurement of the size of the femoral head diameter?

A plain pelvic radiograph is usually conducted with the lower limbs in internal rotation. This is to correct the anteversion of the femur. However, in the fracture neck of the femur, internal rotation of the fractured limb is avoided, because it would be painful. We examined the effect of correction of anteversion or otherwise on the diameter of the head of the femur using imaging. This study aimed to determine if there was a significant difference between the femoral head diameter at two different positions, at the normal anatomical position (without correcting the anteversion) and at the corrected anteversion position. It also aimed to document the correlation and the statistical significance between the differences in the size of the diameter at these two different positions with the anteversion angles of the femoral bone. Two sets of digital photographs of the proximal part of 55 non-sexed, non-paired femoral bones were taken. Images obtained were at two positions: normal anatomical (with anteversion uncorrected) and anteversion corrected positions. The diameters of the head of the femur were documented at these two different positions. The anteversion angles and actual femoral head (AFH) diameters were also measured and documented. The femoral head diameters at anatomical positions were persistently larger than those measured after the anteversion was corrected, except in three femoral bones (5%) where no differences were observed. The difference in the two measurements was statistically significant to the anteversion angle of the femoral bone. (P = 0.0005). The means of the two sets of measurements were statistically different from each other. Pairwise correlation showed that both were strongly associated with the AFH diameter but the measurements from images with corrected anteversion had a higher value (0.8166) than the measurements from normal anatomical position (0.7526). The correction of femoral anteversion produced femoral head size measurements that were closer to AFH diameters compared to those without the correction of the femoral anteversion. Femoral anteversion should always be corrected as per protocol.

Impacts of Vermicompost and Farmyard Manure as Organic Fertilizer with Biochar Amendment on Soil Quality, Growth and Yield of Sunflower

Background: Sunflower is an economically important and the fourth most valuable oil seed crop. The study aimed to investigate organic fertilizers as an alternative method of enhancing soil quality and to determine the optimal combination of organic fertilizer treatments for sunflower growth performance and yield. Methods: The sunflower variety BARI Surjamukhi-2 was used in this study. The treatments were applied as T1= Control; T2= Farmyard Manure @ 2 t ha-1; T3= Vermicompost @2 t ha-1; T4= Biochar @2 t ha-1; T5= Farmyard Manure @1 t ha-1+Vermicompost @ 1 t ha-1; T6= Farmyard Manure @1 t ha-1+Biochar @1 t ha-1 and T7= Vermicompost @ 1 t ha-1+Biochar @1 t ha-1. Result: The data showed that application of different organic fertilizer treatments improves soil quality. Organic fertilizer addition had a positive effect on the growth traits like plant height, leaves number plant-1, stem diameter, chlorophyll content, head diameter, fresh and dry seed number head-1, 1,000-seed weight and seed yield. The correlation results strongly agreed that chlorophyll content, fresh seed number, head diameter plant-1 and 1,000-seed weight could be considered as selection indices for high yield of sunflower. This demonstrates the organic fertilizer’s capacity to improve sunflower growth and yield, as well as its significant potential to replace chemical fertilizers in the perspective of crop sustainability.

Using preoperative planning software to assess the effect of head length on prosthetic range of motion in a high-risk population: a three-dimensional modeling study.

Concurrent use of minus heads with tapered stems in total hip arthroplasty (THA) decreases the prosthetic range of motion (pROM). Three-dimensional preoperative templating can simulate the location of the impingement by taking the hip through a virtual pROM. This enables surgeons to simulate how modifying the type of implant, orientation, and position influences impingement. We hypothesized that CT-based modeling would result in a decrease in the pROM, thereby increasing the risk of impingement when minus heads are used. Forty-three patients who underwent robotic-assisted primary THAs were included. Prosthetic head diameter (32/36-mm) and head length (minus/zero/plus) were the predictors. Maximum external rotation at full hip extension and internal rotation at 90° and 100° of flexion prior to prosthetic impingement were the outcome variables. A CT-based preoperative planning software was used for pROM estimation and impingement detection. Significant decreases in pROM were found for both head diameters as the head length decreased and was more pronounced in external rotation during full hip extension (changes of 2.8-3.4° for the 32-mm head and 1.6-2.8° for the 36-mm head (p = 0.00011)). The magnitude of loss in pROM when using a minus head was larger than the gain provided by a plus head in tapered stems (p < 0.0001). Head length affects the offset and pROM. When the use of minus heads or smaller heads is indicated, 3D preoperative templating for assessing postoperative pROM and impingement provides surgeons with options to consider alternate surgical plans offering additional assurance and protection from dislocation.

Sunflower germplasms’ response to different water and salinity stress levels in greenhouse and field conditions under subsurface drip irrigation

AbstractSunflower (Helianthus annuus L.) is moderately tolerant to salt and water stress, but its production can still be significantly and adversely affected by increases in these stressors as a result of the negative impacts of climate change on agricultural soil and crop productivity. The morphological and productivity (dry head weight, dry root weight, dry shoot weight, head diameter, whole seed weight, crude protein content, crude oil content, palmitic acid, stearic acid, oleic acid, linoleic acid, eicosanoic acid, 11‐eicosenoic acid, homo‐gamma‐linolenic w6 acid, lignoceric acid and plant height) responses of modern sunflower germplasms to different levels of salt and drought stress under greenhouse and field conditions were investigated and analysed. Six germplasms were evaluated under three salt concentrations (0, 150 and 250 mM), and two germplasms were evaluated for drought response under three irrigation levels. Significant differences in the response of sunflower germplasms to water and salinity were detected. The same germplasms exhibited significant differences in response to water and salinity between the treatments, which also varied significantly between the germplasms for the same treatment. The irrigation level significantly influenced the amount of oil but not the crude protein or fatty acid composition. The results and information of this research can aid in selecting and improving sunflower productivity under adverse (i.e. saline and drought) conditions.

Effect of Transplanting Time and Nitrogen–Potassium Ratio on Yield, Growth, and Quality of Cauliflower Landrace Gigante di Napoli in Southern Italy

Research has been increasingly focusing on the preservation of the biodiversity of vegetable crops under sustainable farming management. An experiment was carried out in southern Italy on Brassica oleracea L. var. botrytis, landrace Gigante di Napoli, to assess the effects of two transplanting times (9 September and 7 October), in factorial combination with five nitrogen–potassium ratios (0.6; 0.8; 1.0; 1.2; and 1.4) on plant growth, yield, and quality of cauliflower heads. A split-plot design was used for the treatment distribution in the field, with three replications. The earlier transplant and the 1.2 N:K ratio led to the highest yield, mean weight, and firmness of cauliflower heads which were not significantly affected by both transplanting time and N:K ratio in terms of colour components. The 1.2 N:K ratio led to the highest head diameter with the earlier transplant, whereas the 1.0 ratio was the most effective on this parameter in the later crop cycle. The highest nitrate, nitrogen, and potassium concentrations in the heads were recorded with the earlier transplanting time. Antioxidant activity, ascorbic acid, and polyphenol content increased with the rise of the N:K ratio. The element use efficiency was constantly negative with the N:K increase for nitrogen and was augmented until the 1.2 ratio for potassium. The results of our investigation showed that the optimal combination between transplanting time and N:K ratio is a key aspect to improve head yield and quality of the cauliflower landrace Gigante di Napoli, under the perspective of biodiversity safeguarding and valorisation.

Intraoperative live measurement of femoral head size for acetabular cup sizing: simple, accurate, and green!

Templating is the first step in achieving a successful total hip arthroplasty. We hypothesize that native head size is highly correlated with implanted cup size. Therefore, the purpose of this study is to look for a correlation between sizes of the intra-operative measurement of the femoral head and the implanted cup. This is a monocentric observational study conducted from December 2018 till January 2023. All patients admitted for a primary total hip arthroplasty were included and retrospectively reviewed. Intra-operative femoral head measurement, radiographic femoral head diameter, templated (planned) cup size, and definitive implanted cup size were recorded. The sample included 154 patients (85 female and 69 males) with a mean age of 66.2 ± 10.4years. There were 157 THA cases; 82 on the right side and 75 on the left side. The native head size and acetate template on digital radiographs were the most significantly positively correlated with cup size (P < 0.0001) while the radiological head size was significantly negatively correlated with cup size (P = 0.009). The implanted cup was on average 2 ± 2mm bigger than the native head size measured intra-operatively. The native femoral head diameter measured intra-operatively is a simple and reliable tool to help the surgeons choose the proper size of the acetabular cup, preventing complications during surgery hence optimizing results post operatively. This technique would contribute to a more ecofriendly orthopaedic reconstructive surgery.

Cross-process chain influence of process variations in self-piercing riveting with regard to semi-finished product dimensions

Semitubular self-piercing riveting is an important and well-established mechanical joining process. A new approach, which involves the use of high strain hardening rivet materials, has the potential advantage of increasing resource efficiency in rivet production by eliminating the normally necessary post-treatment of the rivets by means of heat treatment and coating. However, as the high strain hardening of the rivet materials leads to extraordinarily high tool loads during rivet forming, process fluctuations can be particularly critical. For example, fluctuations in the dimensions of the semi-finished products used can influence the forming process itself, but also the quality of the formed rivets, which in turn can affect the subsequent joining process and the joint formation. An increased reject rate or premature tool failure caused by this is detrimental to the resource efficiency of the entire process chain. Therefore, a fundamental knowledge of the cross-process chain cause-and-effect relationships in conjunction with fluctuating billet dimensions is needed and is acquired within this research work. The investigations show that the forming and the joining process as well as the manufactured components themselves are influenced by the billet dimensions. The forming forces and tool stresses rise with increasing billet volume. Tool failure due to excessive or uneven stress can be the result. As the billet volume increases, the head diameter and the head thickness of the rivets increase. Consequently, the joining process and the joint are also indirectly influenced by the billet volume. With increasing volume, the joining force rises and, due to the increase in the head diameter, so does the joint strength. Knowledge of the detailed relationships is therefore highly relevant for the successful use of high strain hardening rivet materials.

Investigation of heat exchanger tube fitted with triangular perforated nail head twisted‐tape inserts

AbstractA numerical investigation of the Nusselt number, heat transfer augmentation efficiency, and friction factor in a laminar flow tube with triangular perforated nail head twisted tape (TPNHTT) is reported using ANSYS 19.2 Fluent. The effects of triangular cut (each side 3 mm) in the middle pitch of the tape along the height, diameter, and top diameter of the nail head (10, 2, and 2.5 mm, respectively) have been explored for (300 ≤ Re ≤ 1800) in a tube of 22 mm diameter. In this paper, implementation has been done with a TPNHTT varying width (14 ≤ b ≤ 20) twist ratio (TR) ranging from (3 ≤ TR ≤ 6), inserts in a tube for laminar flow. Twisted tape (TT) produces a swirl flow associated with fluid resulting in heat transfer enhancement and pressure drop characteristics other than that for the plain tube (PT). The performance of the Nusselt number and friction factor increased up to 123.62% and 495.30%, respectively, on the application of TPNHTT as compared with PT. A maximum thermal performance efficiency of 2.98 has been achieved using the twisted‐tape ratio of the current tube in laminar flow at a Reynolds number of 1700. In addition, correlation equations (11) and (12) have been developed for the friction factor and Nusselt number valid for 300 ≤ Re ≤ 1800, 14 ≤ b ≤ 20, and 3 ≤ TR ≤ 6. The study has proved that applying TT is an upgraded approach for laminar convection heat transfer. This novel work finding will be supportive for researchers to design the latest heat exchangers.